declare #main-input has (binary-mode | text-mode | buffered | unbuffered)
#main-input is read from in text mode: this is the default setting for non-UNIX systems.
Additionally, by default
#main-input is buffered.
declare #main-input has allows this
behaviour to be changed explicitly. Changing both the mode and the buffering is possible, but requires two
declare #main-input has binary-mode declare #main-input has unbuffered
This declaration should always be used in preference to the
newline declaration for performing
binary input or output.